1. Field of the Invention
This invention relates to paint mist removing apparatus, and more particularly to a paint mist removing apparatus having a constricted passage for allowing a gas laden with overspray paint mist from a spraying chamber to flow at high speed, along with a cleaning liquid, down to an exhaust chamber. The constricted passage includes a liquid shooting section for scattering the cleaning liquid toward a cleaning region formed in a lower portion of the constricted passage, while reducing the cleaning liquid to fine droplets in the gas flowing down the constricted passage.
2. Description of the Related Art
As shown in FIG. 7, a paint mist removing apparatus of the type noted above has a constricted passage 12 including a cleaning region S1 disposed below a passage inlet 12a and defining a droplet thick region where cleaning liquid W is dispersed from a liquid shooting section H1 while being reduced to fine droplets. In the cleaning region S1, the liquid droplets capture overspray paint mist in a passing gas A, thereby removing the overspray paint mist from the gas A. The cleaning region S1 providing the droplet thick region is formed in an intermediate portion of the constricted passage 12 where the gas flow is maintained at high velocity. This assures a higher mist capturing efficiency than the cleaning region being formed downstream of the constricted passage 12 where the gas flow is considerably decelerated upon discharge from the constricted passage 12 to an exhaust chamber 11.
Conventionally, this type of paint mist removing apparatus, as shown in FIG. 7, has the constricted passage 12 including only one cleaning region S1 below the passage inlet 12a, and only one liquid shooting section H1 to cooperate with the cleaning region S1.
A still greater efficiency of capturing overspray paint mist is demanded today. Attempts have been made to promote the mist capturing efficiency by diminishing a sectional area of the constricted passage 12 to increase gas velocity, or by causing an increased quantity of cleaning liquid to flow through the constricted passage 12 along with gas A. The diminished sectional area of the passage or increased quantity of cleaning liquid results in a greater pressure loss in the constricted passage 12. This brings about a disadvantage of greatly increasing noise (mainly noise of the scattering cleaning liquid) leaking from the constricted passage 12 to a spraying chamber 1, thereby worsening working environment in the spraying chamber 1.